1. Field of the Invention
The present invention relates to an electric wiring block which is used to connect together wiring harnesses or electric devices provided in the interior portion of a vehicle, and includes electric parts such as fuses, relays and the like.
2. Description of the Related Art
At the present, a vehicle is automatically controlled and carries an AV device and a navigation apparatus on board. An inevitable consequence of is that in wiring members such as a wiring harness, a connector and the like for the purpose of safety, fuses in a vehicle are increasing in number. In order to connect such wiring members, fuses and the like efficiently as well as to simplify the maintenance thereof, an electric wiring block as shown in FIG. 38 is being used (see Japanese Patent Unexamined Publication No. Hei. 6-233434).
One electric wiring block A is a junction box which is interposed between wiring harnesses for a vehicle. The electric wiring block A includes connectors 101 and a fuse block 102 on the surface thereof, and further includes, in the interior portion thereof, an electric circuit which is composed of a bus bar 103. Also, the other electric wiring block B is a relay box which includes a relay socket 104 on the surface thereof and further includes, in the interior portion thereof, an electric circuit which is composed of a bus bar 105. The electric wiring block B is fitted into a cut-away space 106 formed in the electric wiring block A and is then fixed thereto by securing claws 107 and stepped portions 108.
A terminal 103a of the bus bar 103 stands up on the surface of the electric wiring block A, while a terminal 105a of the bus bar 105 stands up on the end portion of the electric wiring block B in correspondence to the terminal 103a.
As shown in FIG. 39, with the electric wiring block B connected to the electric wiring block A, if a fusible link 110 is fitted with them, then the electric circuits of the bus bars 103 and 105 are connected with each other through the fusible link 110. Also, a protection cover 111 is placed over the terminal 103a to insulate and cover the same when the electric wiring block B is not used.
Also, conventionally, there is disclosed a fuse block 120 which can be used in common and widely with respect to various circuits (see Japanese Utility Model Unexamined Publication No. Hei. 5-11289). As shown in FIG. 40, the fuse block 120 includes a plurality of terminal insertion and connection portions 124 which are so formed as to face the block surface 120a of the fuse block 120 and also into which respective tab terminals 123 of each of fuses 122 of a blade type can be inserted for connection. In particular, in the fuse block 120, a transverse distance L.sub.X and a longitudinal distance L.sub.Y between the two mutually adjoining terminal insertion and connection portions 124 are respectively set equal to a distance L between the respective tab terminals 123 of each fuse 122.
However, in the above-mentioned electric wiring block, since the fuse block 102 provided on the surface of the electric wiring block A, the electric wiring block B consisting of a relay box, and the like are respectively molded as integral bodies, they are not able to cope with the presence or absence of the electric parts such as a relay, a fuse and the like which depend on the specifications of vehicles. Thus some of the housings can be vacant, with the result that the material costs of the vacant housings and the space used for the vacant housings are wasted.
Also, since the above-mentioned blocks are not compatible with other kinds of vehicles, not only can they not be used at all with other kinds of vehicles, but also the elements of these blocks are not able to follow the changes of the circuits subject to the change of manufacturer's specifications or to cope with the options of various vehicles.
Also, in the fuse block 120, only one kind of fuse can be easily provided on the surface of the fuse block 120. However a connection operation to connect a connecting terminal to an electric conduction passage such as a bus bar-or the like from the back surface of the block 120 is necessary, so that the fuse block 120 cannot be applied to other kinds of electric parts such as a relay and the like.
Further, in the fuse block 120, since the bus bars wired in the respective receiving chambers 124 or terminal insertion and connection portions 124 are large in size, when the specifications of the vehicle are changed, there are portions of the fuse block that are not used. In other words some of the bus bars and receiving chambers are wasted, which raises an inconvenient problem.